Chapter 8: Lipids and Lipoproteins

Question 1

Chylomicrons

Answer 1

Transport dietary or exogenous triglycerides from the intestines to the liver

Question 2

Very-low-density lipoproteins (VLDL)

Answer 2

Transports endogenous triglycerides from the liver to muscle and adipose tissue

Question 3

Low-density lipoproteins (LDL)

Answer 3

Principle lipoprotein carrier of cholesterol to the body’s tissues; most atherogenic lipoprotein and is a major risk factor for coronary heart disease (CHD)

Question 4

High-density lipoproteins

Answer 4

Returns cholesterol to the liver to form bile acids that are excreted in bile; called the “good” lipoprotein snd provides protection against CHD

Question 5

Hyperlipidemia

Answer 5

Total cholesterol is the most often ordered screening test; approximately 70-75% of total cholesterol is carried by LDL, 15-20% by HDL, and 5-10% by VLDL and chylomicrons

Question 6

Hypercholesterolemia

Answer 6

Increased cholesterol that leads to an increase in LDL; associated with hypothyroidism and uncontrolled diabetes mellitus

Question 7

Hypocholesterolemia

Answer 7

Decreased cholesterol; associated with hyperthyroidism and hepatocellular disease

Question 8

Hypertriglyceridemia

Answer 8

Associated with acute pancreatitis

Question 9

Lipoprotein (a)

Answer 9

Causal risk factor for atherosclerosis

Question 10

Cholesterol oxidase

Answer 10

Most common enzymatic procedure; 1) hydrolysis of cholesteryl esters by cholesterol esterase
2) free cholesterol is oxidized by cholesterol oxidase, yielding hydrogen peroxide

Bilirubin, ascorbic acid, and hemoglobin compete with this oxidation reaction

Question 11

Total cholesterol formula

Answer 11

Total cholesterol = VLDL + LDL + HDL

Question 12

Friedewald formula

Answer 12

LDL cholesterol = total cholesterol - (HDL + VLDL)

Not valid if the patient’s triglyceride level is over 400 mg/dL

Question 13

Gel electrophoresis

Answer 13

HDL migrates fastest towards the anode